package com.example.wx.utils;

import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;

public class SHA1
{
    /**
     * sha1加密
     *
     * @param data
     * @return
     * @throws NoSuchAlgorithmException
     */
    public static String sha1(String str) throws NoSuchAlgorithmException
    {
        if (str == null || str.length() == 0)
        {
            return null;
        }
        char hexDigits[] = {'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f'};

        try
        {
            MessageDigest mdTemp = MessageDigest.getInstance("SHA1");
            mdTemp.update(str.getBytes("UTF-8"));

            byte[] md = mdTemp.digest();
            int j = md.length;
            char buf[] = new char[j * 2];
            int k = 0;
            for (int i = 0; i < j; i++)
            {
                byte byte0 = md[i];
                buf[k++] = hexDigits[byte0 >>> 4 & 0xf];
                buf[k++] = hexDigits[byte0 & 0xf];
            }
            return new String(buf);
        } catch (Exception e)
        {
            return null;
        }
    }
}
